1. Field of the Invention
The present invention relates to a method for making an ice slab or artificial snow.
2. Description of the prior art
One of the methods for making artificial snow in an artificial skiing field is a method for making artificial snow by freezing spray atomized water using compressed air (or other compressed gas) into an atmosphere having a temperature of the freezing point or lower. However, this method is not profitable because the equipment is expensive to install and a lot of compressed air is necessary.
The official gazette of Japanese Patent Publication No. 36635/1990 discloses a method for making artificial snow by aerating wet water absorbent polymer with added water at less than the water retention capacity of said water absorbent polymer, thereafter freezing it. For this method, however, the aerated granular wet water absorbent polymer is a gel. Therefore, to scatter the gel on the slope of the skiing field, it is necessary to transfer the gel by compressed air. It is also necessary to separately prepare an ice slab for protecting the pipes equipped on the floor for refrigeration where coolant circulates.
Moreover, to collect melted artificial snow and reuse it by cleaning it with water, it is necessary to adjust the amount of absorbed water after cleaning and dry the collected water absorbent polymer. Therefore, the method is not profitable because operation is complex.
The specification of U.S. Pat. No. 3,251,194 discloses a method for making a skating rink by freezing water absorbent polymer and water but it does not disclose a method for making artificial snow using specific water absorbent polymer and specified amount of water.
The present invention provides a method for making an ice slab for protecting a freezing system equipped on the foundation of the artificial snow field and/or powdery artificial snow for covering the ice slab by a simple system and operation.
Particularly, the present invention provides a method for making an ice slab and powdery artificial snow with a single operation by freezing the fluid aqueous slurry of granular wet water absorbent polymer which is laid up on a horizontal or sloped floor.